Dial combination for radio apparatus



. PIERRE!- DII; COMBINATION: FOR RADIO APPARATUS led May 27, 1941 "Miu up .ni'

June 19', 194s.

Patented June 19,l 1945 UNITED STATES OFFICE- vDIAL COMBINATION FoanAmoArrnATus i i Joseph Pierrel, Newfybrkg-N. Y Application May .27, 1941, serial N6. 395,423 1oc1aims... (o1. 11a-124m*- Myfinveriti'on#frelates".to indicating 'dials used lirriconnectiorrnwith radio apparatus.

, 'The object of 'my inventionis aradio dial that will in particular render iteasier for the general publiicfto,v tunein Shortwave transmitters r `gen- One `.preferred embodiment of my Y invention combines -on the 'dial chart,x not too'large vfor being'acceptable-` to they general public, of a yradio receiver' the following features:

(a) The complete scale of the present short waverange from about (S0-'meters to aboutr 15 meters; s I

(17)"Su11icient bandspread'in particular for the-transmitter 'groupings nowvcommonly known as international broadcast bands; sojthat the lis-l tener Vnmay be abley lto -logl a station more conveniently; l

' v(cRoom for substantially allv of the station designations of said international broadcast bands; that is Vto .sayat present, of aboutr three hundred ftransmitters; plus about f oneV hundred sl'i'ort'vvave transmitters distributed all over V-the short Waverange:

Thoseyfeatures seemto bef-exclusive of-each other-but=thyare not-so by the use offmy invention;

- Still-'other faturesfare-provided which will be disclosed inv4 th'efollowing or will'rbe apparent to: thoselskilled in the art. j v l The means bywhich vI realizev my invention consists essentially inr the interposition, between the tuningmeans and the corresponding-indicating mea'nsf of an appropriate'gearing means accompanied, "on ythe dial chart, by a coiled calimation-scale; a turn indicator'indicating o n whichY turn of the1coiled'y scale the position `of the tuning device has to be read off; and'eventually 'asuitablestaggering,` around the rotational circle of-yfthe coiled calibration scale; of predetermined transmittei-` groupingsV such( as 'n the international broadcast bands; also asuitabledisplacement arrangement for-'tuningindiciag all'as described in th'evfollowing andillustrated in-v the drawing.

v ention'. Rigi-f :1 ,represents .a front :view :of the dial chart. Fiez 2;represents;V anf` alternate displacement arrangement notV shown in Fig. 1. Fig.- 3 gives .a ,si-deeviewy and .cross section. s respectively of fthe gearingmeansg-Eig 4 shows-.avariation of the dialf,;;in-,-frontview.= Beginningzmy detailed description with Fig'.z 3, wey have; thereA -ga-pointer f a whichV :for one 1809 rotation of the ftuning condenser c will vmakesix full1-, turns, ias.- the/two.-l zcogwheels. 1- andss Aare -in the.-pr oportion of 1 vto,-12.,. n

Corresponding-to these sixjull turns described by the pointer av fwe have fonvthegd-iala chart, Iin Fig. 1, six concentric scales-IlfQEs..Gr.,fI-I.,` J and K which are yiny reality the sixturns .of onewsingle scale extending from- 5,300 ;kc. .to/19,700ikcs. coiled togetherinforder tof occupy, less spaces Alongsideth'ose-- six :scale turns f we -havejf the arcuatefspacesfC; Fi I :andf-Ldestined. A'to lreceive a certain knumber; of Istation#designations.`

As the-'outer ones ofathe vsix turns f of. the `coi-led scale,.the turnsJ and K-,aresituated at a greater distanceufromf the center; of? rotation gthey. show more* calibrationfspread -thanfthe .inner turns :D and y E 1 this iis .snol disadvantage, as more/@transmitters yof public interest'are distributed overthe lower frequenciessof -ztheishort Waverange .than over the -fhigherffrequencies land more space has to be provided, inv theladjoiningv arcuate spaces I andL, Vforrthe station` :designations offthe lower frequencies. As to the.particularly numerous .sta-v tiorrdesignations of thev` international broadcast bandsgtheyl are dealt with inl aspecial manner. as sh'owvnafurtherlbelow. c

A means had to be provided toindicateonwhich onefofthe vSix-turnsscf lthe lvcoiledscale the actual positionyoff theapointer- 11;. Wthtits successive A revolutionsshas; tofbei read-V om To this`` end f a second. @pinten b ,is l mounted concentrically .with pointerfa-:iandgeared-:to `the tuning-means 4in the ratiofof/Z to 1 by means of the cogwheels t and u, onFig, 3a: This fslowsmoving-.pointer b willthereforedescribe-aan'4 arcffof '60?- everytime the.; fast movingfspointera :describes a full circle, =and=the position of :the `pointer-bf in. the feldsd,x e, g, hn on k respectively. lof, fthe-yarcuatespace Afin,- -Figif .1 will indicate-that the.A pointer afhaslto bereado on the scale: .turn-DVE, l Cral-1,1.I.oItKfrespectively If thereffare 'ongthe dial :chart lother scales L of thesordinaryrkind.pthatfis, scalessthat have not been coiledgthey mayy be:used inconnection with the .slowapointembfwhich thus.,w vin thoselcases; becomes annairrinclicatingpointerrasideY of, its. function;` aswturnifindicator for the coiled scalef o1? scales. Thus in Fig. 1 pointenb isfthefindicating means for the broadcast scale B and for the medium wave scale M, the fast pointer a being eventually used as a Vernier pointer in those instances.

The outermost scale N, on Fig. 1, is a'general precision tuning scale divided in 240 divisions (one division for every ten kilocycles in the six turns of the coiled scale).

As to the numerous station designations of the international broadcast bands, they could not be accommodated in the arcuate spaces C, F, I and L without greatly increasing the latters width, which in turn would unduly enlarge the dial chart. On the other side, by far the largest part of the thus widened arcuate spaces would remain empty as the international broadcast bands occupy only a small fraction of the short wave range.

One of the means to solve the problem is t project those international broadcast bands, in the direction of the pointer bar, into a space especially provided for them; and in order not to have them overlap in thatV space. those international broadcast bands are staggered, that is to say, they'come to lie in different arcs of the rotational circle of the indicating means.

This staggering is'obtained by giving the gearing means a suitable ratio of development which, in the case of Figures 1 and 3 is, as already mentioned, 1 to 12. It is obvious that'several suitable staggering arrangements may be found, depending on the developing ratio of the gearing means andthe capacity or inductance variation of the tuning means. Y

If the projection of transmitter groupings takes place on a dial chart that is fiat or conical, it is advisable to effect the projection away from the center lof rotation, thus providing additional bandspread for those-particularly interesting, projectedparts of the short wave range.

Thus we have in Fig. 1, beginning with the upper'lright hand corner and progressing in clockwise direction, the 19 meter band R projected out of scale E, the V16 meter band S projected out of scale D,th e 49 meter band U projected'out of scale K, the 25 meter band X projected out of scale H, and the 31 meter band Y projected out of scale rJ No international broadcast bands have been allotted yet that would fill the spaces-T, V, W andy G; future 44, 40, 36,y 28, 22 and 18 meter b'ands'rnay be located there. t

Along the "general'scale N are repeated, in bandspread, the'projected calibration groups O of the international broadcast bands, thus greatly facilitating tuning.- 4

A second means to provide space, this'time within the group of turns of the coiled scale itself, for the numerous station designations of' the in'- ternational broadcast bands consists in enlarging the space destined to receive the s tation designations locallvby shifting out of place, in the direction ofthe pointer bar, the portion of the scale, or scales, situated opposite the said international broadcast band, as has been shown for the 19 meter `band, in m on Fig. 2'. The section, containing the transmitter groupings with'the numerous station designations. itself may be shifted as has been shown, on the same Fig'. 2, in n for the V,16 meter band. Letters p andl q mark the places where the two couples of scales that had been shifted out of place are shifted back in line with the rest of their respective scales.

Shifting aswell as projecting take place in the direction ofthe pointer bar as construed lying over the shifted bar.

As lthe spaced allotted Ito the station designations of the international broadcast bands must be ratherwide in order to accommodate the three or four or even more stations sometimes transmitting on the same wavelength, and as knowing the transmitting schedule is of importance in short wave listening, the idea suggested itself to arrange the station designations of the international broadcast bands in their allotted space in such a way that their position in that space would indicate their transmission schedule.

As indicated on Fig. 1 in Q, at the upper right hand corner beginning of the projected internationalbroadcast bands, this space is divided into 24 concentric parts' corresponding to the 24 hours of. theday'. -The station designations are placed within ther limits marking the beginning and the end of the transmission, eventually with such additional indications as daily, "Sunday, irregulan etc. Abbreviations will have to be used when lthe'time of transmission is too short for the wholename.l Thoseabbreviations may be explained-.in'thexfour triangular spaces at the four corners of the dial chart.

Since: transmittingstations change their frequency,. and "since new :transmitters ,come in and old ones drop out, itis advisable torrmake the dial chart exchangeable by any suitable arrangement knQWn inthe, art. Such printed replacementdial charts couldgbe furnished to the owners of receiving sets about three or four Itimes a yearby anV agencyv equipped for rendering that serv1ce,-'- i Y As in SfFig. l 'the international broadcast bands have been'projected preferably sideways in order to place the names asihorizontally as possible and facilitate their reading, space is left empty in the middle, at the bottom as well as at the top, of the front panel, and where'may'be'located the controls AA, BB-andCQ, and the 4,openings P for the loudspeaker, Thus, `in spite of the large amountot tuning information given-by the dial chart, the whole can be embodied on .the front panelof a'relatively small receiver,A for instance abattery operated receiver -to be taken out into the country side.` f i Thel size of the receiver can be further reduced by constructing the dial in such manner that the two sides of the dialv chart can be folded over the middle along the dotted lines-fw' and ww (Fig. 1), thusforminga cover for the front panel when the receiver is *notin-l use.4 It' would be preferable, in that case, to avoid the folds ou' and ww' passing through the body of station designations by featuringthe latter altogether on the movable flaps on horizontal lines in vertical column, the connection between the station designations andthe pointer being established by featuring the frequency number of -the transmitters induplicate, once in the arcuate scales O and once alongside of the station designations in the vertical column y as indicated in Fig. 4.'

"The arrangement of Fig. 4 may also be found preferablev when bulk is not a problem and where the'lists of station designations -on both sides of the central' dial chart are not mounted on movablediaps', but on the' adequately enlarged receiver cabinet itself. if

Staggering' of the' transmitter groupings that are to befprojectedis no strict requirement in the 'casefof Fig. 4ias' only'sectionsof the calibration scaleare yproperly projected, that is, projected in the-direction of lthe pointer bar. Since said sections are rather narrow bands two of them may,in- `the -caser'of overlapping, easily 4be laid parallel to `eachotl'ier, :instead -of.' beingsstrictly in'single Aiile, without unduly lincreasing vthe size ofthe dialchart:

What has been describedhferefin detailfor the international broadcastbandsA can ,of course also bedone in regard to the amateur bands and any other transmitter groupings, in any yfrequency `range of the radio spectrum,-andfo'rfy transmitting apparatus as well.

While I have thus shown and described my invention in some of its preferred forms, it is expressly understood that I do not wish to be limited thereto, but include all the various embodiments to which the principles here disclosed may apply.

I claim:

l. In radio apparatus having a continuously variable tuning means, rotatable indicating means including a dial chart and pointer adapted for indicating the setting of said variable tuning means, gearing connecting said indicating means with said tuning means for imparting to said indicating means a rotational movement of more than 360 for each complete movement of the tuning means from its position of maximum capacityto its posi-tion of minimum capacity, a calibration scale on said dial chart extending about the center of rotation of said indicating means through more than 360 in lsuccessive said tuning and main indicating means for indieating, on a separate, auxiliary scale, on which turn of said calibration scale to read the actual y position of said tuning means.

2. An apparatus according to claim l in which the turn indicating means is arranged to rotate concentrically with the main indicating-means.

3. An apparatus according to claim 1 in which at least one additional calibration scale extends about the center of rotation through no more than 360 and in which the turn-indicating means is arranged to rotate concentrically with the main indicating means and to serve simultaneously as a conventional indicating means in co-operation wi-th said additional calibration scales.

4. An apparatus according to claim l in which the gearing has a development ratio such as to result in the relative staggering of predetermined transmitter groupings contained in at least two turns of at least one calibration scale extending about the center of rotation through more than 5. An apparatus according to claim 1 in which the turn-indicating means is arranged to rotate concentrically with the vmain indicating means, in which the gearing has a development ratio such as to result in the relative staggering of predetermined transmitter groupings contained in at least two turns ofl at least one calibration scale extending about the center of rotation through more than 360, in which tuning indicia in at least one section of at least one turn of at least one calibration scale extending about the center of rotation through more than 360 are displaced in the direction of the pointer, and in which station designations are located, within a vspace divided into twenty-four collimating bands corresponding to the twenty-four hours of a day, across such of the hour calibrations as correspond to the transmission schedule of the designated station.

6. An apparatus according to claim 1 in which the gearing has adeveloprnent ratio such as to result in the relative staggering of predetermined transmitter groupings located in at least two turns of at least one'calibration"scale extending 1 about the center of Vrotation' `through moreA 'thanY 360, 'andi-in which at leastone ofsaid staggered transn mitter--g'roupingsis projected; in thedirection of 'thevpointen into-aapredetermined space' divided intoftwenty-four collimating bands representing thetwenty-four hours-of a day; and station designations :placed acrossv such ofthe hour calibratinsas correspond to the transmission schedule of the designated station; 'v1- f i '7. An apparatus according to claim 1 in which at least one additional calibration scale extends about the center of rotation through no more than 360, in which the turn-indicating means is arranged to rotate concentrically with the main indicating means and to serve simultaneously as a conventional indicatingv means in co-operation with said additional calibration scale, in which said gearing has a development ratio such as to result in the relative'staggering of predetermined transmitter groupings contained vin at least two turns of at least one calibration scale extending about the center of rotation through more than 360, in which the dial chart is flat and at least one of said staggered transmitter groupings is projected, in the direction of the pointer into a space farther removed from the center of rotation of the tuning means thereby providing increased bandspread for the thus projected transmitter grouping, in which said space is dividedsin twenty-four concentric bands representing the twenty-four hours of the day, and in which the station designations of the projected transmitter groupings are placed across such of said concentric hour calibrations as correspond to the transmission schedule of the designated station.

8. An apparatus according to claim 1 in which additional calibration scales extend about the center of rotation ory said indicating means through not more than 360, in which the turnindicating means is arranged to rotate concentrically with the main indicating means and to serve simultaneously as a conventional indicating means in co-operation with said additional calibration scales in which the dial chart is ilat and in which sections of calibration scales are projected, along the direction of the pointer, into a space further removed' from the center of rotation of said indicating means than said calibration scales whereby additional bandspread is provided for said projected sections of said calibration scales.

9. An apparatusI according to claim l in which the turn-indicating means is arranged to rotate concentrically with the main indicating means, inswhich the gearing has a development ratio such as to result in the staggering of predetermined transmitter groupings contained in at least two turns of at least one calibration scale exindicating means is arranged to rotate'concen-- trically with .the main indicating means and to serve simultaneously asA a conventional indicating means c ofoperationwith said additional calif bration scales, in Which said gearing basa development ratio such as to result in "thestaggering of at least one transmitter grouping contained `Ain a calibration scale extending around-the center of rotation through more than 360, relativelyto at least one transmitter grouping contained inya calibration scale extending around the center of rotation through not 4more than 360; in which the various parts of the dial chart are at different 10 distances froid theaaxis lof1,rotation-1.0i theiridi-4 eatingV means, and in. whichatransmtterfgroupings are projected, along the direction of the-rele.- vant pointer, into a space farther removed from the center of rotation; oflsaidindicating'means than said-calibration scales, to thereby provide additional bandspread foi-said projected transmitter groupings.

JOSEPH PIERREL. 

